Electric switch contact



Oct. 13, 1931. T, R, -rm 1,827,533

ELECTRIC SWITCH CONTACT Filed April 9, 1928 Patented Oct. 13, 1931 THOMAS RICHARD MARTIN, OF TYSELEY, BIRMINGHAM, ENGLAND ELECTRIC SWITCH CONTACT Application filed April 9, 1928. Serial No. 268,647.

This invention relates to electrical sockets for attachment plugs of the blade type, and has generally in view to provide a novel contact member and a novel assembly of the same with a socket base or body.

' Special objects of the invention areto provide a socket base or body and a contact member which are so constructed as to materially facilitate assembly of the contact member with the socket base or body in a correctand rigid manner, and to provide a contact member which may be economically produced from' sheet metal.

With the foregoing and other objects in View, the invention consists in the novel features of construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawings and defined in the apso pended claims.

In the drawings, wherein are illustrated practical embodiments of the invention:

Figure 1 is a central vertical section through an electrical socket constructed in accordance with the invention.

' Figure 2 is an elevation of the socket looking toward the left hand side thereof as viewed in Figure 1. v

Figure 3 is a bottom plan view of the socket.

Figure 4 is a perspective view of the contact member shown in Figures 1 to 3; and

Figure 54s a perspective view of an alternative embodiment of the invention illustrating the cooperating parts of the socket in separated relation.

Referring to the embodiment of the invent-ion illustrated in Figures 1 to 4, a designates the body or base of the socket which is formed from insulating material and which may conveniently take the form of a substantially cylindrical block as shown. In

accordance with the invention, this block is formed with a substantially central cavity al which opens through one end of the block, and with a cavity a2 which opens through the side of the block, the two cavities being separated by a wall 44 in which is formed a slot a3 for a purpose which will presently appear.

An insulation cover 03 is provided for the end of the block athrough which the cavity a1 opens, and through said cover is formed a slot 031 for the insertion of the blade of a circuit continuing plug into the cavity al. The cover may be secured to the block by screws or in any other suitable or desired manner.

The contact member for use with the socket body or base illustrated in Figures 1 to 3 is formed from sheet metal into substantially S-shape and comprises the two parallel terminal arms 10 and 11 and the parallel intermediate portion 12, one end of which is connected with the adjacent end of the terminal arm 10 by a yoke portion 13, and the other end of which is connected with the adjacent end of the terminal arm 11 by a yoke portion 14. The contact member thus comprises two separate U-shaped formations disposed in reversed relation.

As best shown in Figure 4 of the drawings, the intermediate portion is longitudinally slit as at 62 adjacent to its edges and said slits are continued inward a limited distance across the yoke portion 14 to provide a contact tongue 6 which is bent to extend parallel to the terminal arm 11 relatively close thereto and for cooperation therewith to pro vide a plug blade socket.

In assembling the contact member with the socket base or body a the U-shaped formation comprised by the terminal arm 10, the intermediate portion 12 and the yoke portion 13 is engaged over the wall a4 in straddling or embracing relation thereto, and the U-shaped formation comprised by the terminal arm 11, the intermediate portion 12 and the yoke portion 14 is disposed within the cavity (11 with the free ends of the arm 11 and the cooperating contact tongue I) facing the end of the base through which the cavity a1 opens. This is clearly illustrated in Figure 1 of the drawings, from which figure it is apparent that due to the yoke portion 13 of the first-mentioned U-shaped formation extending across the end of the wall a4, application of the cover 0? to the base a serves, by engagement with said yoke portion, to secure the contact member rigidly in assembly with the base with the slot (21 alined with the space between the contact arm 11 and the tongue 6, whereby a plug blade is insertable through said slot into engagement with said arm and tongue.

The arm 10 of the contact member has a binding screw a threaded therein for the purpose of attaching a conductor to the contact member, and the heretofore mentioned slot a3 is provided in the wall a4 of the socket base or body to accomodate the inner end of said binding screw as shown in Figure 1.

According to the alternative embodiment of the invention illustrated in Figure 5, the socket base or body a is provided with a substantially central cavity a5 which opens through one end of the base and with a cavity a6 which opens through the side of the base, as in the embodiment of the invention illustrated in Figures 1 to 4:, but instead of there being a wall a4 separating said cavities, as in the first described embodiment of the invention, the cavities a5, a6 are in communication with each other and two spaced flanges a7 project inward a limited distance from each of the two opposite side walls of the cavity a5 at points between the cavity a6 and the inner wall of the cavity a5. Moreover, the contact member according to this embodiment of the invention is of substantially U-shape and comprises the parallel terminal arms 64, 65 connected together at adjacent ends by the yoke element 63, and this yoke element is slit to provide the pair of contact tongues 67 which are bent to extend parallel to the terminal arm 65 and to cooperate therewith to form a plug blade socket.

In assembling the contact member of Figure 5 with the base illustrated in said figure the U-shaped socket formation constituted by the terminal arm 65, the contact tongues b and the'yoke portion connecting said arm and tongues, is disposed within the base cavity a5, and the terminal arm 64. which carries the binding screw 01 is disposed in the cavity (16, the yoke portion of reduced width formed by the bending of the contact tongues 67 therefrom being received between the adj acent faces of the two pairs of flanges a7. The

contact member thus is held against lateral movement relative to the base, and to secure the contact member in assembly with the base a block 6 is inserted between the flanges a7 into engagement with the yoke portion of the contact and a cover (not shown) similar to the cover 0? is fastened over the end. of the base through which the cavities a5, a6 open for engagement with the outer edge of the block e to hold the latter in a position clamping the contact member in assembly with the base. As shown, the block 6 is provided with a slot e1 'to accommodate the inner end of the binding screw 02, and the arm 64 of the contact member preferably is flanged outwardly as at 66 to be engaged by the cover to assist in holding the contact member in assembly with the base.

Manifestly, according to each embodiment of the invention, the contact member includes a U-shaped contact portion comprised in one instance by the contact arm or tongue 11, contact tongue I) and yoke portion 14, and in the other instance by the arm or tongue 65, the contact tongues 67 and the yoke 63, and in both embodiments of the invention the contact member is inclusive of a portion forming an outward continuation of the yoke portion of the U-shaped contact formation and disposed parallel to the arms or tongues of such formation to constitute a means whereby the contact elements may be secured in assembly with their respective base members.

In view of the foregoing it is believed that the construction and the advantages of the invention will be apparent. It is desired to point out, however, that while specific embodiments of the invention have been illustrated in the drawings, the invention is readily capable of being embodied in other mechanical structures within the spirit and the scope of the invention as defined in the apappended claims.

I claim:

1. An electric switch contact comprising abase, a cover and a contact member adapted to be clinched between said cover and base and comprising a n shaped locating and a U-shaped socket portion, one limb of said socket portion being constituted by a portion bent from an adjacent limb of said locating portion.

- 2. In an electric plug socket, a contact member inclusive of a portion of U-shape comprising a pair of spaced cooperating contact tongues and a yoke portion connecting said tongues, and an extension from said yoke portion disposed outwardly with respect to said contact tongues parallel thereto and through the instrumentality of which the contact is adapted to be mounted on a support.

3. In an electric plug socket, a contact member inclusive of a portion of U-shape comprising spaced cooperating contact tongues and a yoke portion connecting said tongues, and an extension from said yoke portion disposed outwardly with respect to said tongues parallel thereto and through the instrumentality of which the contact is adapted to be mounted on a support, one of said contact tongues being constituted by a portion of said extension bent therefrom.

4. An )electric plug socket comprising a base having a recess therein opening through an end thereof, a wall between one side of said recess and the adjacent side of the base, a contact member inclusive of a portion of U-shape comprising a pair of cooperating contact tongues and a yoke portion connecting said tongues disposed within said recess,

an extension from said yoke portion disposed outwardly with respect to said tongues and cooperating with said wall to hold the contact member against lateral movement relative to said base, a cover for said base, and means wherebysaid cover retains said contact member in assembly with the base.

5. An electric plug socket comprising a base having a recess opening through an end thereof, a wall between one side of said recess and the adjacent side of the base, a contact member inclusive of a U-shaped socket port-ion disposed within said recess and a locating portion of inverted U-shape straddling said wall, and a cover for said base cooperating with the locating portion of said contact member to retain the latter in assembly with, the base. I

6. In an electric plug socket, a contact member of S-shape comprising two outer arms and an intermediate portion, a yoke connecting one end of said intermediate portion with the adjacent end of one of said outer arms, a second yoke connecting the other end of said intermediate portion with the adjacent end of the other outer portion, said intermediate portion being slit to provide a contact tongue and said tongue being bent for cooperation with one of said outer arms to provide a plug blade socket.

7. An electric plug socket comprising a base having a recess opening through an end thereof, a wall between one side of sa1d recess and the adjacent side of the base, a contact member of S-shape comprising a pair of outer arms, yokes connecting opposite ends of said intermediate portion with ad acent ends of said outer arms, respectively, to provide a pair of U-shaped formations disposed in inverted relation to one another, one of said formations straddling said wall, the intermediate portion being slit to provide a contact tongue and said tongue being bent for cooperation with the outer arm of the other formation-to provide a plug blade socket disposed Within the recess in said base, and a cover for said base cooperating with the U-shaped formationwhich straddles said wall to retain the contact member in assembly with the base.

8. In an electric plug socket, a contact member of U-shape inclusive of a pair of arms and a yoke portion connecting said arms, said yoke portion being slit to provide a contact tongue and said tongue being bent for cooperation with one of said arms to provide a plug blade socket.

9. In an electric plug socket, a contact member of U-shape inclusive of a pair of spaced parallel arms and a yoke portion connecting adjacent ends of said arms, said yoke portion being slit to provide a pair of tongues, and said tongues being bent to extend between said arms substantially parallel thereto for cooperation with one of said arms to provide a plug blade socket. V

10. An electric plug socket comprising a base having a recess therein opening through an end and a side thereof, a contact member of U-shape disposed within said recess, and a block slidably engaged with said base and cooperating with said contact member {)0 retain the latter in assembly with said ase.

11. An electric plug socket comprising a base having a recess therein opening through an end and a side thereof, a contact member of U-sha e disposed within said recess, and a block s idably engaged with said base and cooperating with said contact member to retain the latter in assembly with said base, said contact member being inclusive of a pair of spaced parallel arms and a yoke portion connecting said arms, said yoke portion being slit and having a tongue bent therefrom for cooperation with one of said arms to provide a plug blade socket, and said block 00- operating with said contact member between said tongue and the other arm thereof.

In witness whereof I have hereunto set my hand.

THOMAS RICHARD MARTIN. 

